1. Field
Apparatuses and methods consistent with exemplarily embodiments relate to a display apparatus for a uniform screen.
2. Description of the Related Art
In general, display apparatuses display screens and include monitors and TVs.
Various types of display apparatuses such as display apparatuses using a cathode ray tube (CRT), display apparatuses using a light emitting diode (LED), display apparatuses using an organic light emitting diode (OLED), display apparatuses using an active-matrix organic light emitting diode, display apparatuses using a liquid crystal displays, display apparatuses using an E-paper display, and the like have been used.
A display apparatus generally includes a display panel optically displaying an image and a backlight unit (BLU) providing light to the display panel.
In general, a display panel does not emit light. Thus, the display panel displays an image for example, by receiving light from a backlight unit disposed at a rear surface of the display panel.
As a light source of the backlight unit, a cold cathode fluorescent lamp (CCFL) has been conventionally used. However, light emitting diodes (LEDs) have also recently been widely used in various fields due to advantages in terms of weight, thickness, power consumption, color range, switching time, lifespan, and the like.
Backlight units may be generally classified into edge-type backlight units and direct-type backlight units depending on the positions of light emitting diodes that are used as light sources.
The edge type backlight unit includes light emitting diodes disposed to emit light to an edge of a light guide plate. The light guide plate may change the direction of light emitted from the light emitting diodes and guide it to a display panel. The direct-type backlight unit includes light emitting diodes disposed throughout an entire rear surface of a display panel and light may be directly transmitted to a display panel without using a light guide plate.
In the case of the edge type backlight unit, small scratches and foreign substances disposed on a light guide plate may be directly visible on a screen through a display panel. Thus there is a need to pay particular attention to package and transportation of the light guide plate to prevent scratches, resulting in an increase in costs of parts.
In the case of the direct-type backlight unit, a large number of light emitting diodes is generally required, which results in high power consumption required to drive the light emitting diodes. Also, since lenses are generally used in the direct-type backlight unit, an optical distance generally needs to be secured in order to remove hot spots formed on the lenses. In addition, regions of a display apparatus where the light emitting diodes are not disposed are recognized as dark portions, and thus the appearance of a display may deteriorate.